user = input("请输入用户名：")
passw = input("请输入密码：")
if user == "zgj" and passw == "123":
    print("登录成功！")
elif user == "zgj" and passw !="123":
    print("密码错误！")
elif user !="zgj" and passw =="123":
    print("用户名错误!")
elif user !="zgj" and passw !="123":
    print("用户名和密码都错了！")
else:
    print("登录失败！")